During NBC's slow slide to near-irrelevancy in prime time over the past decade, a succession of entertainment executives sat in boardrooms plotting comeback moves that didn't work.

It's still early, but NBC seems finally to have hit upon a plan that is moving things in the right direction. New entertainment chief Bob Greenblatt's baby steps strategy of using the successful competition "The Voice" as its centerpiece has helped NBC stand as the only one of the four big broadcasters to have a larger prime-time audience than it had last fall.

In the 18-to-49-year-old demographic that NBC targets, the network has made a startling move from fourth place to first, winning the first four weeks of the season for the first time since 2002. Among all viewers, it ranks third behind CBS and ABC.

"They needed a hit show to ignite the network," said Marc Berman, an analyst with TV Media Insight, "and now they have it."

Greenblatt, who came to NBC after running Showtime, said he understands the temptation of thinking all a network's problems can be solved at once. Since that hardly ever happens, he brought a lesson he learned from cable.

He decided to set one or two priorities and put all of the network's attention on achieving them. In this case, the plan was to build out from NBC's most successful franchise, the Sunday Night Football game, and improve the nights right after it.

NBC launched its first-ever fall version of "The Voice" and stretched it to two nights a week -- Monday and Tuesday. Greenblatt didn't want to compete directly with Fox's "The X Factor" later in the week, and believed ABC's competing "Dancing With the Stars" was an aging franchise with a graying audience.

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"The Voice" has rewarded his confidence and, just as important, served as a launchpad for new shows that followed it on the schedule, the drama "Revolution" on Monday and the Matthew Perry comedy "Go On" on Tuesday.

Greenblatt's ultimate goal is to broaden NBC's appeal. The network's Thursday night comedies probably have more critical plaudits (and Emmy Awards, in the case of "30 Rock") than they have viewers.

"He's trying to make comedies that people will watch," said Bill Gorman, co-founder of the website TV By the Numbers, "as opposed to comedies like 'Community' and '30 Rock' that have small, rabid fan bases but not a lot of people watching them."

Two nights don't make a complete turnaround, though. Greenblatt recognizes he has challenges before him. Football leaves a hole in NBC's schedule when the NFL season ends this winter. "The Voice" ends its cycle in December and doesn't return until March. Then, popular cast members Christina Aguilera and Cee Lo Green will be missing.

Greenblatt said NBC has a lot of work to do, both in programming and staffing. "It's really a from-the-ground-up rebuild," he said.

"It's a lot of hard work," he added. "We've been in a bad place for much of that, so it's nice to look around in our staff meetings and say it's possible to change fate. There are days when you think it isn't possible. But it's really nice to get some validation that the strategy works. When you have some good shows, that will change all. So we're feeling a lot better than we were."